The present invention relates to improvements in tube welding machines. Tube welding machines include a large number of individual roll stands wherein particularly contoured rolls, for example, pre-shape skelp into a split tube to be welded at the joint. The individual roll stands may, however, be required to process different types of skelp to obtain different diameter tubes to be welded. Therefore, it may be required to exchange the rolls in the individual stands. The present invention, therefore, relates particularly to improvements in the structure which permits the exchange of the rolls in individual stands as pertaining to a tube welding machine.
Known equipment of the type referred to above usually requires that the rolls in each stand are individually disconnected and removed from particular shafts or axles supporting the rolls. This operation is quite cumbersome and time consuming and requires well trained personnel because the work involved requires great skill. It was found, moreover that the exchange of rolls which are horizontally mounted pose particular difficulties, and in many tube welding machines the number of such stands is quite large.
In a completely different state of art, German Pat. No. 1,052,346 discloses subassemblies composed of shafts, mounting pieces and rolls. However, these particular subassemblies are, in fact, not suitable for use in rolling stands of the type customarily employed in tube welding machines, so that therefore these kind of subassemblies have not been used in tube welding machines and in roll stands in such machines.